1. Field of the Invention
The present invention relates to a front end module, and more particularly, to a front end module for wireless network system.
2. Description of the Related Art
Up to the present, the technology of wireless network is divided into two categories. One utilizes a radio wave to make a transmission while another one utilizes light to make a transmission. Examples of the latter are the infrared light and laser served as carrier for data transmission. Since a radio wave has better transmittance than light, it is more flexible in application.
With regard to the wireless network utilizing the radio wave, there are two aspects in the development. One is the blue-tooth technology applied for circumstance of short distance (10 meter), low power consuming (100 mW), and low cost while another one is the IEEE802.11 technology applied for the office (data transmission rate is up to 54 Mbps and the distance can be lengthen to be 100 meter around).
In general, a wireless network system based on the IEEE802.11 technology includes a front end module, a base-band processor (defined as PHY), and a media access controller (MAC).
Since an included front end module always comprises a lot of passive components such as capacitors, resistors, filters, and impedance converters, there are problems of low reliability, high cost, and large volume. Therefore, an attempt to modularize and miniaturize these components in order to solve these problems would be raised.